The jury was shown a DVD which featured forensic scientist Mr Vallance in a bulletproof vest, ear protectors and protective glasses blasting away with the rifle at a target. This was described by defence counsel Thomas Ross, representing Brown, as being in a manner reminiscent of Al Pacino in Scarface. Mr Ross dubbed the footage of Mr Vallance firing the gun as "Over the top productions". Mr Ross said: "What sort of video would there have been if you had used the unrepaired weapon and eight useless bulleted cartridges?"

Mr Vallance replied: "There wouldn't have been any point making a video."

The defence counsel added: "The weapon couldn't do anything?"

Mr Vallance said:"No."

Prosecutor Paul Kearney asked Mr Vallance: "Would you need to be a firearms expert to carry out the repair you did", and he replied: "No."

Earlier in the trial the jury was shown the assault rifle, which was found in a search of a tenement block in Paisley on October 23, 2013. The rifle and a magazine with bullets were in a padlocked cupboard outside the flat. The court heard the weapon was in a black bin bag in the cupboard under a pile of material including deckchairs, Christmas decorations and part of a Hoover. It was wrapped in a sheet and a magazine and bullets were wrapped in a pillowcase and inside a blue Ikea bag and then covered in a bin bag.

The court heard the DNA of James Welsh (54) from Renfrew was on the magazine. He was asked if he could explain this and said the last time he had touched a gun was when he was around 10.

He then added that it could be "contamination or something".

Mr Welsh denied knowing Gary Convery. He was asked why he appeared to have made calls to a phone used from time to time by Convery and said: "I don't know. I can't remember. Maybe we were having a wee chat or something."